30 BC: Cleopatra: Gender Experiment

In the first century B.C. Cleopatra devised an experiment to test the accuracy of the theory that it takes 40 days to fashion a male fetus fully and 80 days to fashion a female fetus. When her handmaids were sentenced to death under government order, Cleopatra had them impregnated and subjected them to subsequent operations to open their wombs at specific times of gestation.